First of all, try eliminating any underlying causes of your insomnia. Basically, the happier you feel, the better you sleep. I hope you have somebody to help you. Everyone, regardless of age, needs physical pleasure - and I don't mean just sexual one, it's any tactile contact with the one you want to be with, it's exercise, it's any feeling your body craves, etc. You owe it to yourself and have no reason to be denied it. By the way, have you had a nice vacation lately?
In addition to this, there are lots of mild herbal remedies, which can be tried separately or in combination, as teas or as tinctures: hops, mint, vervain, passionflower, peony, camomile, motherwort and others; hawthorn, marjoram and thyme are not inherently inducing sleep but are sometimes added as well. I intentionally excluded valerian because of possible side effects of high doses - your ability to process multiple continuous streams of information (e.g. fly a plane) may be impaired, I experienced it once myself. Other than that, these herbs are innocuous enough to experiment with them yourself, but a herbalist's advice may help achieve the result quicker. Usually, the best results are produced by a cocktail of several herbs.
If you drink coffee or strong tea in *any* quantities, even just in the morning, try withdrawing it for a few days and see what happens, but be sure to drink a lot of water (more than beverage withdrawn).